Spring bean爲空

Question

我正在使用jetty 6.1.26作爲web服務器的掛毯，spring，hibernate web-app，並且我無法擺脫userDao bean的nullpointexception（它在application_context_dao.xml ::

public class UserManagerImpl implements UserManager { 

    private UserDao userDao; 

    public void setUserDao(UserDao userDao) { 
     this.userDao = userDao; 
    } 

    public boolean checkLogin (String login, String password) { 

     return userDao.checkLogin(login, password); 

    } 

application_context_dao.xml：

<beans> 

<bean id="userDao" class="org.prikic.projektni.domain.dao.hibernate3.UserDaoImpl"> 
    <property name="sessionFactory"> 
     <ref bean="sessionFactory" /> 
    </property> 
</bean> 

<!-- sessionFactory --> 
<bean id="sessionFactory" 
    class="org.springframework.orm.hibernate3.LocalSessionFactoryBean"> 
    <property name="configLocation"> 
     <value>classpath:hibernate.cfg.xml</value> 
    </property> 
    <property name="configurationClass"> 
     <value>org.hibernate.cfg.AnnotationConfiguration</value> 
    </property> 
</bean> 

<bean id="transactionManager" 
    class="org.springframework.orm.hibernate3.HibernateTransactionManager"> 
    <property name="sessionFactory" ref="sessionFactory" /> 
</bean> 
<bean id="transactionProxy" abstract="true" 
    class="org.springframework.transaction.interceptor.TransactionProxyFactoryBean"> 
    <property name="transactionManager"> 
     <ref bean="transactionManager" /> 
    </property> 
    <property name="transactionAttributes"> 
     <props> 
      <prop key="insert*">PROPAGATION_REQUIRED</prop> 
      <prop key="update*">PROPAGATION_REQUIRED</prop> 
      <prop key="save*">PROPAGATION_REQUIRED</prop> 
      <prop key="*">PROPAGATION_REQUIRED, readOnly</prop> 
     </props> 
    </property> 
</bean> 

的web.xml：

<web-app> 
<display-name>projektni Tapestry 5 Application</display-name> 

<context-param> 
    <!-- The only significant configuration for Tapestry 5, this informs Tapestry 
     of where to look for pages, components and mixins. --> 
    <param-name>tapestry.app-package</param-name> 
    <param-value>org.prikic.projektni</param-value> 
</context-param> 
<!-- Specify some additional Modules for two different execution modes: 
    development and qa. Remember that the default execution mode is production --> 
<context-param> 
    <param-name>tapestry.development-modules</param-name> 
    <param-value> 
     org.prikic.projektni.services.DevelopmentModule 
    </param-value> 
</context-param> 
<context-param> 
    <param-name>tapestry.qa-modules</param-name> 
    <param-value> 
     org.prikic.projektni.services.QaModule 
    </param-value> 
</context-param> 


<context-param> 
    <param-name>contextConfigLocation</param-name> 
    <param-value> 
     /WEB-INF/application_context_dao.xml 
     /WEB-INF/application_context.xml 
     <!-- classpath:application_context*.xml --> 
    </param-value> 
</context-param> 

<filter> 
    <filter-name>app</filter-name> 
    <!-- Special filter that adds in a T5 IoC module derived from the Spring 
     WebApplicationContext. --> 
    <filter-class>org.apache.tapestry5.spring.TapestrySpringFilter</filter-class> 
</filter> 

<filter-mapping> 
    <filter-name>app</filter-name> 
    <url-pattern>/*</url-pattern> 
</filter-mapping> 

任何幫助，將不勝感激......

我不把其他彈簧應用上下文xml文件道歉，那就是：

application_context.xml：

<beans> 
    <bean id="userManagerTarget" class="org.prikic.projektni.services.impl.UserManagerImpl"> 
      <property name="userDao"> 
        <ref bean="userDao" /> 
      </property> 
    </bean> 
    <bean id="userManager" parent="transactionProxy">    
      <property name="target"> 
        <ref bean="userManagerTarget"/> 
      </property> 
      <property name="transactionAttributeSource"> 
        <bean class="org.springframework.transaction.annotation.AnnotationTransactionAttributeSource"/> 
      </property> 
    </bean> 
</beans> 

Index.java：

import org.apache.tapestry5.annotations.Persist; 
import org.apache.tapestry5.annotations.Service; 
import org.apache.tapestry5.annotations.SessionState; 
import org.apache.tapestry5.beaneditor.Validate; 
import org.apache.tapestry5.ioc.annotations.Inject; 
import org.prikic.projektni.services.UserManager; 

public class Index { 

private static final String BAD_CREDENTIALS = "Bad login and/or password. Please retry."; 


//private boolean error = false; 
@Persist 
private boolean error; 

@SessionState(create=false) 
private String login; 

@Inject 
@Service("userManager") 
private UserManager userManager; 

private String password; 

public String getLogin() { 
    return login; 
} 

@Validate("required") 
public void setLogin(String login) { 
    this.login = login; 
} 

public String getPassword() { 
    return password; 
} 

public String getErrorMessage() { 
    String ret = null; 
    if (error) { 
     ret = BAD_CREDENTIALS; 
    } 
    return ret; 
} 

@Validate("required") 
public void setPassword(String password) { 
    this.password = password; 
} 

String onSuccess() { 

    String ret = "Index"; 
    error = true; 

    boolean s = userManager.checkLogin(login, password); 

    if (s) { 
     error = false; 
     ret = "Home"; 
    } 
    return ret; 
} 

}

Answer 1

因爲它缺少配置中的片斷，我認爲這是完全不存在：

<bean id="userManagerImpl" class="org.prikic.projektni.domain.dao.hibernate3.UserManagerImpl"> 
    <property name="userDao" ref="userDao"/> 
</bean> 

加入這個bean到Spring配置之後，它應該工作。當然現在你不能只是打電話：

new UserManagerImpl(); 

因爲Spring對這個類一無所知，所以不能執行依賴注入。我不知道Tapestry，但看起來你已經在使用TapestrySpringFilter，似乎以某種方式將Spring與Tapestry相提並論。 JavaDoc中說，它是：

暴露出每個bean在它作爲一個掛毯的IoC服務

如果使用這種所謂的IoC服務並以某種方式獲得UserManager情況下，你會被罰款。